By the end of this chapter you will be able to:

• Re-run a Task Plan after failure
• Rollback a Task from the Console
• Rollback and re-run a Task from the Console

Re-running a Task Plan after failure

Using the model you created during the Introduction to Modelling course, or if you do not have this the reference model Intro to Modelling 10: Generating Alarms, you will update a Database Collector so that the collection fails:

• Open the Database Collector Last bill amount/ Last bill amount R
• Edit the query so that it will fail. E.g. update the name of the table being read from SOURCE_CUST_BILLS to SOURCE_CUST_BILLS_ERR.

Run the Task Plan you created in exercise 1. You will see an error. Look at the Stream Sets in each of the Streams (and Alarm Generators) in the model. You will see that everything "downstream" of the Database Collector Last bill amount/ Last bill amount R has an incomplete (yellow) Stream Set.
Undo your update to Last bill amount/ Last bill amount R so that the query is correct again. Run the Task Plan. You will see that only the incomplete Stream Sets are generated – and that in the Streams which successfully completed in the previous run, no new Stream Sets are generated.
Find the log for this second run, and go to the Stream Sets tab. You will see that some of the Stream Sets are marked in red, and in the Status field there is an icon with description (if you hover over the icon) Show the log which created this Stream Set. These are the Stream Sets that were generated in the previous run of the Task Plan. If you press on this icon it will take you to the log of the task that generated this Stream Set.

Rolling back a Task from the Console

Find the log file for the second run of your Task Plan during the previous exercise. Go to the Stream Sets tab.
Press the button Rollback all data... . CenterView will rollback all the Stream Sets from that run.
Run your Task Plan again. Note that the Stream Sets generated by this new run have the current date and time – so the model is now more up-to-date than from the previous run.

Rolling back and re-running a Task from the Console

Find the log file for the final run of your Task Plan during the previous exercise. Go to the Stream Sets tab.
Press the button Rollback data and run the analysis again... .
In the log file you found at the start of this section, you will now see an icon in the Status field to indicate that this task has been re-run. Press this to open the log file for the new run of the task.